com.pervasive.datarush.io

Class BinaryReader

java.lang.Object

java.io.InputStream

com.pervasive.datarush.io.BinaryReader

All Implemented Interfaces:

Closeable, AutoCloseable

Direct Known Subclasses:

SplitInputStreamImpl

public class BinaryReader
extends InputStream

Provides extended data access methods on binary data flows. Beyond supporting a byte-oriented view of the concatenated tokens, a number of methods for reading primitive type binary formats are provided. BinaryInputStream is also extended to provide support for reading from other "chunked" byte sources.

See Also:

BinaryBuilder

Field Summary

Fields

Modifier and Type	Field and Description
protected long	absolutePosition The total number of bytes read
protected byte[]	buffer The current token value
protected int	position The offset of the next byte to read in the token
protected int	size The size of the current token
protected InputStream	source The underlying byte stream

Constructor Summary

Constructors

Constructor and Description
BinaryReader(byte[] bytes) Wraps a byte array with a byte-oriented reader.
BinaryReader(InputStream source, int bufferSize) Wraps an InputStream with a byte-oriented reader having extended function.

Method Summary

Methods

Modifier and Type	Method and Description
int	available()
void	close() Closes the wrapped port and releases any allocated resources.
long	getAbsolutePosition() Gets the current position in the underlying data.
boolean	isEmpty() Indicates whether the byte stream for reading has been exhausted.
void	mark(int readlimit) Marking the stream is not a supported operation.
boolean	markSupported()
int	read()
int	read(byte[] b)
int	read(byte[] b, int off, int len)
int	readBase128Int() Reads a base-128 encoded int value from the stream.
long	readBase128Long() Reads a base-128 encoded long value from the stream.
byte	readByte() Reads a single byte from the stream.
byte[]	readBytes(int len) Reads a specified number of bytes from the stream.
char	readChar() Reads a character value from the stream.
char[]	readChars(int count) Reads a specified number of character values from the stream.
double	readDouble() Reads a double value from the stream.
float	readFloat() Reads a float value from the stream.
int	readInt() Reads an int value from the stream.
long	readLong() Reads a long value from the stream.
char[]	readSingleByteChars(int count) Reads a specified number of character values from the stream, assuming the bytes are the least-significant bytes of the values.
int	readUnsignedBase128Int() Reads a base-128 encoded int value from the stream, assuming an unsigned encoding.
long	readUnsignedBase128Long() Reads a base-128 encoded long value from the stream, assuming an unsigned encoding.
void	reset() Resetting the stream is not a supported operation.
long	skip(long n)
void	skipBytes(long count) Advances the read position in the stream the specified number of bytes.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

source

protected InputStream source

The underlying byte stream

buffer

protected byte[] buffer

The current token value

position

protected int position

The offset of the next byte to read in the token

size

protected int size

The size of the current token

absolutePosition

protected long absolutePosition

The total number of bytes read

Constructor Detail

BinaryReader

public BinaryReader(InputStream source,
            int bufferSize)

Wraps an InputStream with a byte-oriented reader having extended function. If an IOException is thrown by the wrapped source, the provided stream will be closed.

The wrapped stream should not be accessed directly after creating the stream. Doing so may result in unexpected or otherwise unpredictable behavior in both the stream and the wrapper.

Parameters:

source - the stream to wrap

bufferSize - the size of the read buffer to use, in bytes. Data will be read in chunks of this size from the wrapped stream.

BinaryReader

public BinaryReader(byte[] bytes)

Wraps a byte array with a byte-oriented reader.

Parameters:

bytes - the byte array to wrap.

Method Detail

read

public int read()
         throws IOException

Specified by:

read in class InputStream

Throws:

IOException

read

public final int read(byte[] b)
               throws IOException

Overrides:

read in class InputStream

Throws:

IOException

read

public final int read(byte[] b,
       int off,
       int len)
               throws IOException

Overrides:

read in class InputStream

Throws:

IOException

skip

public long skip(long n)
          throws IOException

Overrides:

skip in class InputStream

Throws:

IOException

available

public int available()

Overrides:

available in class InputStream

getAbsolutePosition

public final long getAbsolutePosition()

Gets the current position in the underlying data.

Returns:

the number of bytes read so far

markSupported

public final boolean markSupported()

Overrides:

markSupported in class InputStream

mark

public final void mark(int readlimit)

Marking the stream is not a supported operation.

Overrides:

mark in class InputStream

Throws:

UnsupportedOperationException - always

reset

public final void reset()

Resetting the stream is not a supported operation.

Overrides:

reset in class InputStream

Throws:

UnsupportedOperationException - always

close

public final void close()

Closes the wrapped port and releases any allocated resources. Subsequent reads will behave as if end of data has been reached.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class InputStream

isEmpty

public boolean isEmpty()

Indicates whether the byte stream for reading has been exhausted.

Returns:

true if no more bytes are available to be read, false otherwise.

skipBytes

public void skipBytes(long count)

Advances the read position in the stream the specified number of bytes.

Parameters:

count - the number of bytes to skip

readByte

public byte readByte()

Reads a single byte from the stream. The read position is advanced one byte as a result.

Returns:

the byte at the current position

readBytes

public byte[] readBytes(int len)

Reads a specified number of bytes from the stream. The read position is advanced the specified number of bytes.

Parameters:

len - the number of bytes to read

Returns:

the next len bytes starting at the current position

readChar

public char readChar()

Reads a character value from the stream. The read position is advanced 2 bytes.

Returns:

the character value encoded at the current position

readChars

public char[] readChars(int count)

Reads a specified number of character values from the stream. The read position is advanced 2 bytes for each character requested.

Parameters:

count - the number of characters to read

Returns:

the next count characters starting at the current position

readSingleByteChars

public char[] readSingleByteChars(int count)

Reads a specified number of character values from the stream, assuming the bytes are the least-significant bytes of the values. The read position is advanced only one byte for each character requested.

Parameters:

count - the number of characters to read

Returns:

the next count characters starting at the current position

readInt

public int readInt()

Reads an int value from the stream. The read position is advanced 4 bytes.

Returns:

the int value encoded at the current position

readUnsignedBase128Int

public int readUnsignedBase128Int()

Reads a base-128 encoded int value from the stream, assuming an unsigned encoding. The read position is advanced to the position following the last byte of the encoding.

Returns:

the int value base-128 encoded at the current position

See Also:

BinaryBuilder.appendUnsignedBase128(int)

readBase128Int

public int readBase128Int()

Reads a base-128 encoded int value from the stream. The read position is advanced to the position following the last byte of the encoding.

Returns:

the int value base-128 encoded at the current position

See Also:

BinaryBuilder.appendBase128(int)

readLong

public long readLong()

Reads a long value from the stream. The read position is advanced 8 bytes.

Returns:

the long value encoded at the current position

readUnsignedBase128Long

public long readUnsignedBase128Long()

Reads a base-128 encoded long value from the stream, assuming an unsigned encoding. The read position is advanced to the position following the last byte of the encoding.

Returns:

the long value base-128 encoded at the current position

See Also:

BinaryBuilder.appendUnsignedBase128(long)

readBase128Long

public long readBase128Long()

Reads a base-128 encoded long value from the stream. The read position is advanced to the position following the last byte of the encoding.

Returns:

the long value base-128 encoded at the current position

See Also:

BinaryBuilder.appendBase128(int)

readFloat

public float readFloat()

Reads a float value from the stream. The read position is advanced 4 bytes. The bytes are interpreted using Float.intBitsToFloat(int).

Returns:

the float value encoded at the current position

readDouble

public double readDouble()

Reads a double value from the stream. The read position is advanced 8 bytes. The bytes are interpreted using Double.longBitsToDouble(long).

Returns:

the double value encoded at the current position

toString

public String toString()

Overrides:

toString in class Object